Apparatus for applying protective coating material to the inside of a pipe or the like



I. LOUDENBACK ET AL March 28, 1950 I APPARATUS FOR APPLYING PROTECTIVE COATING MATERI TO THE INSIDE OF A PIPE OR THE LIKE 2 Sheets-Sheet 1 Filed Aug. 17, 1945 J m a P l. LOUDENBACK ETAL 2,501,779

COATING MATERIAL TO THE INSIDE OF A PIPE OR THE LIKE March 28, 1950 c,

APPARATUS FOR APPLYING PROTECTIVE 2 Sheets-Sheet 2 Filed Aug. 17, 1945 \i. 1 v m I Hw w E Q c WW. I

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Patented Mar. 28, 1950 APPARATUS FOR APPLYING PROTECTIVE COATING MATERIAL TO THE INSIDE OF A PIPE OR THE LIKE Clyde 1. Loudenback, Ferndale, Mich., and Alfred C. Riesen, Chicago, Ill., assignors to Deal-born Chemical Company, Chicago, 111., a corporation of Illinois Application August 17, 1945, Serial lilo. 611,024 Claims- (Cl. 91-44) This invention relates to improvements in apparatus for applying protective coating ma.- terial to the inside of a pipe or the like and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

One of the objects of the present invention is to provide simple and efllcient apparatus for quickly applying to the inside of a pipe or the like, and this in a manner assuring complete coverage thereof with an even thickness or layer. a coating material of a type usually requiring heat to reduce it to proper consistency.

Another object of the invention is to provide apparatus of this kind which is capable of use when sections of pipe are Joined end to end in long lengths.

Also, it is an object of the invention to provide apparatus of this kind which is economical in the amount of coating-material employed and is easy to handle so that pipe sections may be interiorly coated as rapidly as said sections can be joined end to end in the laying thereof in a trench or the like.

Furthermore. it is an object of the invention to provide apparatus for the purpose mentioned which includes a novel applicator head of simple construction and which will not readily clog with the protective coating material employed and which may be readily taken apartfor cleaning and service and then reassembled in a short period of time without the necessity of special tools.

Again, it is an object of the invention to provide an applicator head for apparatus of this kind, which is not only light in weight so as to be easily handled, but which may be made of relatively small size for use in pipes or the like of small inside diameter.

Still another object of the invention is to provide a novel arrangement for applying coating material and in which the applicator may be controlled from a remote point through the action of the material being applied.

The above mentioned objects of the invention, as well as others, together with the advantages thereof 'will more fully appear as the specification proceeds.

In the drawings:

Fig. 1 is a diagrammatic view in elevation of the improved apparatus when in use in applying a protective coating material to the inside of a Fig. 2 is a view showing the applicator head of the apparatus, when moved into a position in the 2 pipe section different from that appearing in Fig. 1, and which will be described later.

Fig. 3 is a perspective view of one form of applicator head that may be used as a part of the apparatus.

Fig. 4 is a top plan view of the applicator head appearing in Fig. 3.

Fig. 5 is a longitudinal vertical sectional view through the applicator head as taken on the line 55 of Fig. 4.

Fig. 6 is a view in elevation of one end of the applicator head and namely that end at the right hand side of Fig. 5.

Fig. 7 is a transverse vertical sectional view through the applicator head as taken on the line of Fig. 5.

Fig. 8 is a detail fragmentary view in side elevation showing parts whereby the valve in the applicator head may be manually opened from a point remote from the head itself.

Fig. 9 is a view similar to Fig. 5 and shows a modified form of applicator head and wherein the normally closed valve thereof may be caused to open at a certain developed pressure in the head.

. In general the apparatus includes an applicator head of such size as to be capable of insertion into one end of a pipe and then moved longitudinally thereof. This head carries a nozzle out through which coating material is discharged preferably substantially radially so as to be applied in a manner to cover completely the entire interior surface of the pipe, within the range of the nozzle, with an even uniform thickness or layer of such material. Within the head is provided asuitable valve for controlling the discharge of material from the nozzle and which valve is of the self-closing type. In one form of applicator head, this valve may be manually operated from a point remote from the head to open the same and in another form of head, the valve is arranged to open automatically when a certain pressure is developed by the coating material in the head. It is preferred to use a material of such character as to require heat to maintain it in a flowable fluid state for the spraying thereof and the recirculation to which it is subjected in the use of the apparatus.

The head has attached thereto conduit means whereby the coating material in fluid form is delivered to the head from a source of supply remote therefrom. This conduit means is relatively long and one part thereof is rigid and another part is flexible. The rigid part of said means is provided by suitable metal pipe and carries the applicator head and forms the means whereby the head is moved longitudinally in either direction along the inside of the pipe to be coated. The other part of said conduit means is constituted by flexible metal tubing or by rubber or like hose and is connected to a source of supply of the coating material and to a suitable pump equipment. Said equipment is of such capacity that it is capable of'recirculating through the apparatus, a volume of coating material greater than the volume discharged by the nozzle of said head. When the applicator head is moved longitudinally along the inside of the pipe and the valve therein is open, a part of the coating material is sprayed in a radial direction onto the inside surface of the pipe and the excess is returned to the source of supply which is of the kind capable of maintaining the material at that temperature affording the desired consistency.

The apparatus includes, among the parts thereof, a novel applicator head, one form of which is illustrated in detail in Figs. 3 to 7 inclusive and another form of which appears in longitudinal section in Fig. 9.

Referring now in detail to the construction of the applicator head as shown in Figs. 3 to 7 inclusive, said head which is indicated as a whole at It), includes a cylindrical body ll preferably made of brass. In what may be termed the rear end of the body and below its axis is-a pressure chamber l2, the rear end of which is closed by a threaded plug l3. Forwardly of said chamber is a chamber extension [4 of reduced diameter and a valve seat I5 is provided at the junction of said chamber and its extension. In the body forwardly of the chamber extension I is a bore l5 and a packing gland recess ll. At the upper front end of the body is a longitudinally extending tubular boss l8 adapted to have threaded thereinto a coating material discharge member l9 and which member is shown as a radially spraying nozzle in Figs. 1 and 2. The tubular boss I8 is connected by an appropriate passageway 20 with the chamber extension ll.

2| indicates a valve stem that has a sliding engagement in the bore l6 and which carries a valve body 22 disposed in the chamber l2 and normally engaging upon the seat IS. The front end of the stem extends through and beyond a gland nut 23 threaded into recess H which also contains packing material 24. The rear end of said stem has a sliding fit in a recess l3a in the plug I: as best appears in Fig. 5, the recess being so formed as to prevent the forming of an air cushion in said recess in the rearward movement of the valve stem. A helical expansion spring 2| surrounds that part of the valve stem within the chamber I2 between the valve head 22 and plug I3 and which normally urges the stem forwardly to engage the head upon the seat. This makes the valve a self-closing one.

In the upper portion of the body I I is a pair of laterally spaced longitudinal passages 25 and 26 (see Figs. 3 and 7) respectively that are closed at their inner ends. Each passage is connected by ports 21-28 (see Fig. 7) with the pressure chamber l2. Thus the passages 25 and 26 are in communication with each other through the ports 2|--28 and said pressure chamber. The passage 25 constitutes the inlet passage to the chamber l2 for the coating material employed and the passage 28 constitutes the outlet passage from said chamber for said material. when the apparatus is in operation, the material in said chamber [2 is under pressure and assists the spring 24 in holding the valve head 22 upon the seat I5.

Pressure on the front end part of the valve stem, disposed in advance of the gland nut 23 opens the valve and is provided by a cross head 29. Said head is carried by the front end of a pair of longitudinal rods 3I|30 that have sliding engagement in openings 3|--3I, one on each side of and arranged in the plane of the axis of the chamber l2 and valve stem 2| respectively. Thes rods are longer than the body I I so that the rear ends thereof project rearwardly of the associated end thereof. Said rear ends of the rods are connected together by a plate 32 which is fixed thereto by pairs of nuts 33-33. In said plate is an opening 32a to receive one end of an actuator wire 34 which best appears in Figs. 1 and 5.

As before stated, the valve head 22 is normally engaged on the seat I5 and closes ofi communication between the chamber l2 and its extension H and associated passageway 20. To open the valve, a pull on the wire 34 draws the rods 30-30 and cross head 29 rearwardly and causes the cross head to push inwardly on the valve stem 2! against the action of the spring 24 to remove the head 22 from the seat. Thus the material under pressure in the chamber i2 may pass out through the chamber extension II, the passage 20, boss l8 and out through the nozzle [9 which sprays the material in a radial direction. The wire 34 is actuated from a point remote from the applicator head as will be 'mentioned later.

In Fig. 9 is shown an applicator head wherein parts similar to those mentioned bear the same reference numerals.

In this instance the front end of the valve stem 2| extends beyond the gland nut 23 and is provided with a shoulder-like disc 2 la and associated nut 2lb, a spring 24a being disposed to surround that part of the valve stem between the gland nut 23 and disc He. Said spring operates to normally hold the head 22 on the stem closed against or upon the seat l5. Fixed to that part of the valve stem within the chamber l2 at a point rearwardly of the ports 21-28 is a piston 2 is: having a surface area greater than that of the head 22. In this instance the plug 13 is provided with a relief port |3b that opens to atmosphere.

By reason of the difference in effective areas between the piston 2L1: and valve head 22, when the pressure of the coating material in the chamber l2 reaches a certain point, said material will force the piston rearwardly and move the head 22 away from the seat l5 against the action of the spring 24a. This opens the valve, so that material passes to the nozzle 19 for discharge as before described. In this respect the opening pressure will be of such magnitude as to hold the valve open even while the nozzle is discharging the material. When this pressure drops to a certain low pressure, the spring 24a then functions to again cause the head 22 to engage on the seat l5 and close the valve against a discharge of coating material from the nozzle IS.

The apparatus also includes a container for holding a supply (see Fig. 1) of coating material 35 in fluid form and which container in this instance consists of a cart-like tank 36, the material being so constituted as to be maintained at the proper consistency for spraying either by the use of heat or by the addition of a solvent. It is preferred that the material be one that is held at the proper spraying consistency by the use of heat and therefore the container is provided with a suitable burner 31 for that purpose, as appears in Fig. 1.

One form of coating material suitable for the purpose is of a plastic or somewhat elastic nature made with a petrolatum base and is of a heavy grease or wax-like consistency. It may be made from a petrolatum or a mixture of petrolatums having a A. S. T. M. melting point of from about 140 to 175 F. and preferably containing a chemical inhibitor. Material such as just mentioned may be maintained at the desired con-: sistency for eflicient operation when subjected to heat in the tank 36.

Conduit means are provided between said container or tank 36 and the applicator head I6 and such means is duplex in its nature. It is so constituted as to provide an inlet conduit 38 which leads from said container to the applicator head and a return conduit '39. In this instance the conduit 38 is made up of a rigid conduit part 38a and a flexible conduit part 382) in the form of flexible metal tubing or high pressure rubber hose. The conduit 39 is likewise constituted by rigid and flexible parts 39a and 391) respectively.

Each rigid conduit part 38a and 39a is of considerable length, and is operatively engaged at one end in the passages 25 and 26 respectively of the applicator head In and are detachably connected at the other end to the associated flexible conduit parts by couplings Q6 and ti respectively. In the part 39a near the coupling 4| is a quick opening valve 42 to control the passage of fluid through said section. The conduit part 39b is arranged to discharge back into the container 36. The conduit part 381) is connected to the outlet side of a circulating pump 13 driven as by a motor or other source of power M and the inlet side of thepump is connected by a conduit 45 opening into the container 36 at a point near its bottom.

The rigid conduit parts 38a39a are preferably of a length greater than that of the pipe sections which are to be coated on the inside. On the conduit part 38a, conveniently located with respect to the valve 62, is a sliding sleeve 46 (see Fig. 8) having a bayonet slot 4'! therein and carrying a boss 48 to which the wire 34, before mentioned, is attached. A pin 49, carried by the conduit part 38a is engaged in the slot and a collar 50 on said part limits the movement of the sleeve 36 in one direction thereon. With the parts shown as in Fig. 8, the valve head 22 is engaged on the seat i in the applicator head. To open said valve the sleeve is pulled rearwardly toward the valve 42 and when it reaches its limit as defined by the length of said slot 31, said sleeve is turned on the conduit section so that the pin 49 enters the transverse part of the slot. When the sleeve is turned in the other direction, the spring 2.4 operates to return the valve head 22 to its seat H5.

The rigid conduit parts 38a-39b conveniently serve as the carrier for the applicator head and which head can be made of such small diameter as to enter a 2" diameter pipe. For use in larger diameter pipes, a shoe 5! may be attached to the bottom of the body of the applicator head as appears in Figs. 1 and 2.

In Fig. 1 the apparatus is illustrated as in use when applying a protective coating 35:: to the inside of a pipe section 52 of relatively large diameter and having a bell 53 at one end to receive the opposite end of another pipe section to be joined thereto. In operating the apparatus described to carry out the improved method, the

procedure is as follows: Assume that the burner 31 is in operation to heat the material 35 in the container 36 and that the motor 44 is running and is driving the pump 43 and that the valve head 22 is engaged on the seat IS in the applicator head 10. Under the conditions mentioned, the pump is recirculating fluid coating material from the container 36 through the conduit 38 to the pressure chamber l2 in the applicator head and back through the conduit 33 to said container without a discharge of material irom the nozzle l9. The applicator head is thus maintained at a proper temperature to prevent the coating material losing its proper consistency.

The operator now using the rigid conduit parts 38a-39a jointly as a handle for the applicator head 10, inserts the applicator head into the pipe section 52 from its bell end with the shoe 5| engaged on the bottom of the inside of said section. Pushing inwardly on the conduit parts 38a39a slides the applicator head along the bottom of the inside of the pipe until the nozzle I9 on the head is slightly beyond the other end of said pipe section. At this time or prior thereto, the valve 62 is manipulated to build up a suitable pressure in the conduit to applicator head. A suitable gauge (not shown) may be installed in the conduits to indicate the pressure of the material now circulating therethrough.

When the applicator head has been so positioned, the sleeve 36 is grasped and moved rearwardly on the conduit part 38a and then turned to engage the pin 89 in the transverse part of the slot 41. This, through the wire 34, opens the valve in the applicator head. Coating material now passes from the chamber l2 to its extension l4 and out through the passage 20 and nozzle I9 40 to be sprayed radially therefrom. By pulling rearwardly on the conduit parts 38a39a, the applicator head starts its travel toward the bell end 53 of the pipe section 52 while sprayin a part of the material as an even layer or thickness of material 351: on the inner surface of the pipe, and returning the excess to the container. As the pipe surface to which the relatively hot coating material is being applied is relatively cold, the material will congeal and harden and will not "run or curtain toward the bottom of the pipe.

When within a short distance of the bell end of the pipe, as shown in Fig. 2, the sleeve 46 is manipulated to permit the valve head 22 to close on the seat and thus stop the spraying of the material. With the pump still running to maintain the circulation of the coating material through the conduits 3839 so as to prevent coagulation and hardening of the material there-- 60 in, the operator using the conduit parts 38a-39a jointly as a. handle, withdraws the applicator head from the bell end of the pipe section 52.

Another pipe section 52a, shown in dotted lines in Fig. 2, is now joined to the bell end of thefirst pipe section. Thereafter the applicator head is inserted into the pipe section 52a from its bell end 53a and then pushed through the pipe section 52a and into the pipe section 52 to a point slightly to overlap the coating 35m therein. The

70 sleeve 46 is again manipulated as before to restart a spraying of the coating material onto the uncoated surface at the bell end of the section 52 and which will overlap the coating 35a: in said section. The applicator head is then re drawn toward and within a short distance of the bell end 53a of the pipe section 52a. The sleeve 46 is then manipulated to cause the valve head 22 to engage on the seat l as before, so that at this time the material is again being recirculated, as before described. The applicator head may now be withdrawn from the bell end of the section 52a and another pipe section (not shown) be joined thereto and the spraying operation again repeated.

When the applicator head is of the kind shown in Fig. 9, the sleeve 46 and associated parts and the wire 34 are eliminated. In the use of such a head, it is only necessary to actuate the valve 42 to increase the pressure in the conduit parts from the pump 43 to said valve. This increase of pressure builds up in the chamber I! to one sufficient to cause the piston 2 l x to open the valve 22 and hold it open even when such material is being discharged out through the passage 20 and nozzle 19 as a spray. To stop the spraying action, the valve 42 is opened to the extent necessary to cause a pressure drop in the pressure chamber whereby the spring 24a will shift the valve stem 2| forwardly to close the head thereof on the seat I5.

. While in describing the invention we have referred in detail to the form, arrangement and construction of parts, this is to be considered only in the illustrative sense so that we do not wish to be limited thereto except as may be specifically set forth in the appended claims.

We claim as our invention:

1. Apparatus for applying a protective coating material to the inside of a pipe or the like and embodying therein, a supply of fluid coating material, an applicator head carrying a coating material discharge member, means including a conduit for circulating coating material under pressure from said supply through said head and back to said supply, a part of said conduit being flexible and another part thereof which is operatively connected to said head, being relatively rigid and serving as a means for manually moving said applicator head along the inside of the pipe in both directions thereof, and means in said head for controlling the discharge of coating material from said member.

2. Apparatus for applying a protective coating material to the inside of a pipe or the like and embodying therein a supply of fluid coating material, an applicator head carrying a coating material discharge member and including a pressure chamber and a normally closed valve between said chamber and said member, a conduit for delivering coating material under pressure from said suppLvto said chamber, a second conduit for returning coating material from said chamber to said supply, said conduits each including a rigid part and a flexible part and said rigid part serving as a means for manually moving said applicator head along the inside of the pipe in both directions thereof, and means operable from a point remote from said head for causing said valve to open. -3. Apparatus for applying a protective coating material to-the inside of a pipe or thelike and embodying therein a. supply of fluid coating material, an applicator head carrying a coating material discharge member and including a pressure chamber and a normally closed valve between said chamber and said member, a conduit for delivering coating material under pressure from said said supply to said chamber to maintain 9. volme in said chamber greater than that discharged through said discharge member. a second conduit for returning coating material from said chamber to said supply, and a member carried by one of said conduits at a point remote from said head and operable to cause said valve to open.

4. Apparatus for applying protective coating material to the inside of a pipe or the like and embodying therein a supply of coating material, an applicator head having a material receiving pressure chamber therein and a discharge member and including a normally closed valve between said chamber and said member for controlling the discharge of material from said member, a conduit leading from said supply to said chamber in said head, a second conduit leading back from said chamber in said head to said supply, means for causing a recirculation of material from said supply through the first mentioned conduit to said chamber and through the second mentioned conduit back to said supply, means in one of said conduits for controlling the passage of material therethrough and the pressure of said material in said chamber, said conduits serving for manually moving the head along the inside of the pipe in both directions, and means supported by one of said conduits and operative for actuating said valve to open the same at a point remote therefrom.

5. Apparatus for applying a protective coating material to the inside of a pipe or the like and embodying therein a supply of coating material, an applicator head having a material receiving pressure chamber therein and a discharge member and including a normally closed valve between said pressure chamber and said member for controlling the discharge of material from said member, conduit means between said supply and said chamber, means for forcing material from said supply into said chamber under pressure, said conduit means serving as a means for manually moving said head along the inside of the pipe in both directions thereof, and means supported from said conduit means operable from a point remote from said head for actuating said valve to open the same.

6. Apparatus for applying a protective coating material to the inside of a pipe or the like and embodying therein a supply of coating material, an applicator head having a material receiving pressure chamber therein and a discharge member and including a normally closed valve between said pressure chamber and said member for controlling the discharge of material from said member, conduit means between said supply and said chamber and providing a recirculating system therebetween, means in a part of said conduit means for forcing material under pressure and through said system, said conduit means serving as a means for manually moving said head along the inside of said pipe in both directions thereof, and means supported by a part of said conduit means operable from a point remote from said head for actuating said valve to open the same.

7. An applicator head for applying a protective coating material to the inside of a pipe or the like and including a generally elongated body having a chamber therein to receive coating material under pressure, conduits in said body providing for the inlet of coating material under pressure to and the outlet thereof from said pressure chamber, means at one end of the body adapted to receive an applicator member and which means is connected to said chamber by a passageway, a self closing valve in said body having a stem pro- Jecting beyond said one end of the body for controlling the passage of material through said passageway, and rod means longer than said body arranged for sliding movement longitudinally of the body and including a part extending beyond said one end of the body for engaging said projecting stem of said valve a part carried by said rod means beyond the other end of the body, and an actuating element extending from the last mentioned part and in a direction away from the first mentioned part at a location relatively close to the pipe.

8. An applicator head for applying a protective coating material to the inside of a pipe or the like embodying therein a body having a pressure chamber therein and including a portion at one end to receive an applicator member, aself closing valve in said chamber for controlling the passage of coating material from said chamber to the applicator member and including a stem arranged longitudinally of said body, means at the other end of the body for receiving conduits providing the inlet and the outlet for material to and from said chamber, and means having sliding engagement relative to the body and extending parallel with said stem of said valve and operable when moved in one direction to open said valve for the passage of coating material from said chamber to said applicator member.

9. An applicator head for applying a protective coating material to the inside of a pipe or the like embodying therein a body having a pressure chamber therein and including a portion at one end to receive an applicator member, a self-closing valve in said chamber for controlling the passage of coating material from said chamber to the applicator member, and including a stem arranged longitudinally of said body and projecting form said one end thereof, means at the other end of the body for receiving conduits providing the inlet and the outlet for the coating material to and from said chamber, a member slidably supported at each side of the body and parallel with said stem of said valve. a cross bar carried by one end of said members and engaged with said stem, and means connecting the other end of said members and arranged to receive a part whereby said members and cross bar may be caused to be moved to open said valve for the self-closing valve in said chamber for controlling the passage of coating material to said applicator member and including a stem I projecting from one end of the body, longitudinal bores in the body, one spaced laterally from each side of the valve stem, rods slidable in said bores, a cross head arranged outside of said one end of the body and fixed to associated ends of said rods and engaged with said valve stem, a pair of passageways communicating with said chamber and opening through the other end of said body and forming the inlet and the outlet for the coating material to and from said chamber, and a member outside said other end of the body and connected to the other end of said rods and formed for the attachment of an actuating device to open said valve from a point remote from the valve body.

CLYDE I. LOUDENBACK. ALFRED C. RIESEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,758,810 Austin et al May 13, 1930 1,913,757 Hannon June 13, 1933 1,936,247 Hannon Nov. 21, 1933 2,022,481 Schellenger Nov. 26, 1935 2,133,015 Boylan et a1 Oct. 11, 1938 2,185,570 Ridley Jan. 21, 1940 2,194,701 Harrison Mar. 26, 1940 2,348,714 Defiore May 6, 1944 FOREIGN PATENTS Number Country Date 845,052 France May 8, 1939 

